plot explanation - Why did the monkey remain undead in Pirates of the Carribbean?

Even after
the curse was lifted in the first movie, Barbosa's monkey Jack remains undead.

In Dead Man's chest, Jack trades the monkey with the witch
and shot him and pronounced him as undead.

How is that
possible?

Answer

At the end of "Curse of the Black Pearl", after the
credits, there is a scene where Jack (monkey) takes a coin
from the chest - getting himself cursed again, similar to what Captain Jack Sparrow did
during the fight with Barbossa.

Sparrow took the coin
during the fight which he returned later, Jack (monkey) on the other hand
didn't return it. He had probably hidden it with his other
shiny things or lost it somewhere, he is a monkey after
all.

href="http://pirates.wikia.com/wiki/Jack_%28monkey%29" rel="noreferrer">Jack's
complete story.

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